Typically in the manufacturing process of box springs, a first manufacturer constructs a box spring foundation which includes a support surface and a plurality of support modules. The first manufacturer also may attach a box spring base to the support modules. The box spring foundation is then shipped by the first manufacturer to a bedding manufacturer who secures the support modules to a box spring base, if not done by the first manufacturer, and then applies top padding and a cover to complete the box spring. In addition to consumer preference regarding firmness of box springs, storage and shipping costs are additional factors which control the design of box spring foundations and, in particular, support modules used therein.
Many various types of support modules are known which can support rigidly a support surface at a predetermined spacing from a box spring base and which can be inexpensively stored and shipped during the manufacturing process. For example, Schultz, Jr. et al., U.S. Pat. No. 4,377,279, discloses support modules which are hingedly connected both to the support surface and to the box spring base whereby the box spring foundation can be collapsed for storage and shipment. Furthermore, the support modules can be differently configured to allow for total stiffness or varying degrees of recoilable compression.
In Rodgers et al., U.S. Pat. No. 5,346,188, the support modules are hingedly secured to the support surface by the first manufacturer and the support modules are collapsed against the support surface for storage and shipment. When the box spring is to be completed, the bedding manufacturer extends and secures the support modules to the box spring base during the padding and covering process whereby the support modules provide rigid support of the support surface above the box spring base. Schultz, Jr. et al., U.S. Pat. No. 5,622,357, similarly discloses support modules pivotally secured to the support surface, collapsed for storage and shipment, and later extended and secured to the box spring base by the bedding manufacturer with the support modules rigidly supporting the support surface.
Another type of box spring foundation is disclosed in Hagemeister et al., U.S. Pat. No. 5,052,064, in which support modules are fixedly secured to the support surface whereby the resulting box spring foundations can be nestably stacked for shipment and transport. In particular, the support modules are welded to the support surface by the first manufacturer and later stapled to the box spring base by the bedding manufacturer. Hagemeister et al., U.S. Pat. No. 5,361,434, discloses a similar box spring foundation which includes resilient support springs located between the support modules for resiliently supporting localized loads that are applied to the support surface between the localized areas of the support modules.
An object of the present invention is to provide an additional novel and unobvious type of box spring support module which permits the inexpensive storage and shipment of box spring foundations to bedding manufacturers as discussed above.